Standard combined cycle power plants burn fossil fuels. Fossil fuels are also indirectly combusted in standard IGCC (integrated gasification combined cycle) plants, even though typically only H2, CO, or a mixture thereof (syngas) arrives at the gas turbine. The necessity of reducing carbon dioxide emissions has led to discussion of various ways of generating energy from alternative resources.
DE102008031437.4 describes how it is possible to create fully recyclable energy cycles with alkali metals. This has been elaborated in detail in WO2012/038330 and WO2013/156476. The combustion of electropositive metals, such as lithium, sodium, potassium, magnesium, calcium, strontium, barium, aluminum, or zinc is possible in carbon dioxide (CO2) or water (H2O) as well as air. This forms the chemical base materials carbon monoxide (CO) or hydrogen (H2).
This combustion is shown by way of example for lithium in the following reaction equations:Li+CO2→1/2 Li2CO3+1/2 CO−270 kJLi+H2O→LiOH+1/2 H2−202 kJ
Each of the reactions can be utilized to produce the maximum possible thermal energy in a power plant operation similar to a combined cycle (gas and steam) power plant, in the manner of reconversion to power in a gas turbine or additionally in two steam turbines coupled thereto.